network "intrusion" guidance

hello I am in need of a little bit of guidance. My goal of posting this isn't for someone to blatantly tell me how to do this but instead to simply point me in the right direction.

(windows xp sp2) so my goal is to access (intrude) onto my own network from an outside (or an already networked computer) source to view the directory of one of my computers. okay so i know i need to find the ip for that computer, so here is where i have come to a few questions. even while i have the ip how do i view the directory of another computer? is this possible through ms-dos or will i need additional programs? if it would be simpler to just try and access another computers dir while i am already on the net work let me know.

any information will be appreciated, especially if you give me some key terms to research. because what i have come to understand about hacking (even though i am still quite the noob) is that the only way to actually progress is to figure things out yourself...so just a nudge in the right direction is good haha

Well, if you dont have to worry about antivirus, get a trojan like netdevil, or metaldeamon, they work nicely with windows xp, you can also get netcat, that is a very sweet and powerful tool to use on the target computer inconjuction with a batch file to open up a port on target computer for you to telnet to and have total access. The command you must get netcat to execute on the target computer will be: C:\>nc.exe -L -p [specify the port] -d -e cmd.exe
The moment you telnet to the specified port, cmd.exe will execute and you will have full access to that computer. That is one way... The other will be a trojan or a RAT (Remote access tool). Cracking the password will also work, get Cain & Abel to do that, You have Cain on your computer, make a SMB connection to the other computer, steal the password, and use cain to install abel on the target computer, once you have done that, you will have access to his computer in his dos console.